While investigating various high-tech solutions to the challenges of feeding the planet, the editors stumbled on some ideas that were definitely intriguing but just didn’t seem practical. These innovations could someday mature to the point of becoming valuable, though, so we wanted to share them with IEEE Spectrum readers, who we figured might appreciate them. But don’t consume what follows without a good dollop of skepticism.
Make Mine a Mealworm
Earth would be a better place if we ate insects rather than cows. Ready to do your part?
Consider what life would be like if people were rational. There’d be no stiletto heels, no Ferraris, no messy love affairs, no professional sports.
And we’d probably eat bugs.
Throw everything aside except cold logic, and entomophagy, the fancy term for eating insects, makes a lot more sense than what we’re doing now. Cows, pigs, sheep, and chickens are fed on corn and soybeans, valuable crops that we humans also eat. Cows and sheep consume huge amounts of water and require enormous parcels of land on which to graze. And before they are slaughtered, these animals produce solid and gaseous wastes that damage the environment.
Insects have none of those drawbacks. They can consume organic refuse—including spoiled food, rotted carcasses, and even animal excretions. (Hungry yet?) And the protein in an insect is every bit as healthy as what you’re taking in now.
“There’s no reason for people not to eat insects if you consider the nutritional value,” says Arnold van Huis, a professor at Wageningen University & Research Center, in the Netherlands, and the coauthor of a recently published cookbook for insect eaters. Van Huis notes that insects have long been on the menu in less developed parts of the world.
“We are on the verge of starting a new food production chain,” says van Huis, sketching out a vision of big factory farms raising grubs, mealworms, and other larvae for the hungry hordes.
But come on, now. Insects? For dinner? Really? In the developed world, where the price of half a kilogram of ground beef is less than what it costs to dry-clean a shirt?
It’s not going to happen. “You can ask people to jump out of planes, to do all kinds of things,” says Vaclav Smil, an environmental scientist at the University of Manitoba, in Canada. “But you can’t get them to eat bugs.”
Still, interest in entomophagy just won’t go away. “Every day I get mail or a phone call from somewhere in the world,” says van Huis. I don’t have the heart to tell him it’s only because people think his taste for bugs is so bizarre.
—By Glenn Zorpette
Vertical farms provide lots of food—for the imagination
Imagine the hanging gardens of Babylon updated for the 21st century. For Columbia University ecologist Dickson Despommier, among others, putting farms inside high-rise buildings could usher in an era of industrial-scale urban farming. These steel-and-glass greenhouses would tower above megacities, providing cornucopias for the future. At least that’s what the proponents’ 3-D renderings suggest. But nobody has yet built one to test the concept, and it’s possible nobody ever will.
Many experts are deeply skeptical, for a simple reason: Inspiring as these hypothetical structures may be, vertical farms—at least the skyscraper variety—don’t match the demands of photosynthesis. That is, they don’t provide adequate light.
Lucky plants with a window office would receive enough photons, but most would require artificial illumination, which doesn’t do the best job of replicating photosynthesis-fueling wavelengths. Electric lights also require power, and there isn’t yet a green source capable of providing it, at least not without raising the price of lettuce to skyscraping levels.
“We do not have a technology today that can artificially light plants in an economically acceptable or carbon-efficient manner,” says Ted Caplow, an environmental engineer who founded BrightFarms, an urban-greenhouse company based in New York City.
Yet Caplow is quick to add that the Disneyesque world-of-tomorrow notion of farming inside towering buildings serves a purpose. According to him, various farm-in-the-sky renderings have nourished the imagination of urban agriculturists who have come up with more practical arrangements: rooftop greenhouses and agriculturally repurposed buildings of just a few stories. And many such urban greenhouses now exist.
How resource-efficient and economic today’s urban agriculture can be remains to be seen, but even if it proves commercially successful, don’t expect these operations to sprout into skyscrapers. Practical facilities will probably never match the audacious concepts kicking around. “It’s important not to mistake one for the other,” says Caplow.
Raising seafood in offshore cages just isn’t practical
Giant cages full of fish, adrift in the deep blue sea: That’s one vision for the future of saltwater aquaculture, much of which now occurs in near-shore pens, where shallow water and slow currents allow waste to accumulate and diseases to fester. It’s hard to imagine how industry can expand those near-shore operations to meet growing 21st-century appetites, if for no other reason than there’s only so much coastline.
“If we confine ourselves to technology that needs to be anchored in the coastal zone, we’re unable to exploit vast areas in the middle of the ocean,” says Cliff Goudey, former director of MIT’s Offshore Aquaculture Engineering Center, who now heads C. A. Goudey & Associates of Newburyport, Mass.
Goudey’s work includes propulsion systems for the Aquapod, a buckyball-shaped screen cage designed to float far from land. Developed nearly a decade ago by Maine-based Ocean Farm Technologies, it’s one of several such free-floating cages designed for offshore aquaculture. All these systems remain highly experimental, though, deployed only in a few small demonstrations.
Carrying out aquaculture far out to sea, it turns out, poses some thorny issues. Tethering cages to the seabed is too expensive, and towing them around with boats is impractical in rough waters. Ideally, the cages would be self-propelled, so they could fight currents and keep themselves in a suitable location out of shipping lanes. But then fuel would need to be delivered, as would fish food.
Given these expenses, plus competition from existing operations, floating-cage fish farmers would likely raise high-value predatory species beloved of sushi eaters but decried by sustainability advocates because other fish must be caught to use as feed. “Deeper-water fish farming will likely improve environmental footprints, but it’s not clear if it will move toward sustainability,” says George Leonard, a strategist at Ocean Conservancy.
Goudey admits that the economics of floating offshore cages remain daunting. “The major players in marine aquaculture are quite content now,” he says. “The big operators aren’t in this, and the small operators can’t afford it. It’s ahead of its time.”
— Brandon Keim
Out of the Test Tube and Into the Fryer
How much would you pay for a guilt-free hamburger?
“We shall escape the absurdity of growing a whole chicken in order to eat the breast or wing,” wrote Winston Churchill 81 years ago. And although we’re scarcely closer to his vision today, don’t blame the Dutch, who have been pursuing laboratory-grown, or in vitro, meats since 2005.
The latest push began in April 2012, when Mark J. Post, a former medical doctor and vascular specialist at Maastricht University, in the Netherlands, announced that he had received funding from an anonymous American donor to create a synthetic hamburger. Post has missed four target dates for the syn-burger unveiling but is reportedly aiming to have it ready any day now.
In vitro meats would have many advantages. The most important are the environmental benefits that would come from not having to sustain more than a billion water-consuming, greenhouse-gas-belching livestock on the 26 percent of the planet’s land they now occupy. You’d also avoid the twinges that many people feel about eating an animal that must be slaughtered and butchered in a process as labor intensive as it is gruesome. And besides, artificial meats could be engineered to have only healthy fats and in whatever proportion that is most pleasing to the palate.
“It’s not difficult science,” says Isha Datar, who runs New Harvest, which advocates for in vitro and other meat alternatives. “It’s more of an engineering problem. It’s ‘How do we do this in a cost-effective way?’ ”
In vitro meats, like ordinary ones, are actual animal muscles and fat. So they have to be fed nutrients and grown, and even stimulated and exercised, in some sort of bioreactor. No one yet has any idea how to do that cheaply. Pundits have estimated that Post’s burger will cost more than US $300 000. Besides Post’s project, there is a small commercial effort in Columbia, Mo., where the start-up Modern Meadow is attempting to use 3-D-printing technologies to produce edible biological tissues.
Datar thinks we should regard in vitro meat as just one part of a future “portfolio” of meat alternatives, serving different markets and tastes and at different price points. “It would make more sense than relying on the extremely inefficient system that we rely on now,” she asserts. Taking her advice would certainly avoid, as Winston might put it, a lot of blood, toil, tears, and sweat.
Field of Dreams
A pulsed electric field can be used to cook food—or at least make it edible
The French technique sous vide (slow, low-temperature cooking under vacuum) now has some competition. Engineers at Wageningen University & Research Center working with the Dutch companies OMVE and IXL Netherlands, have devised a new cooking method they call Nutri-Pulse, which is said to rival sous vide for preserving nutrients but works much faster.
How much faster? Even the toughest cut of beef would take minutes instead of hours. Is that fast enough for you?
Nutri-Pulse cooks by applying pulsed electric fields of 1000 to 4000 volts per centimeter, which cause tiny holes to form in the cell membranes of the item being cooked. So things are made edible and pathogens are killed, as in conventional cooking, but with only a mild rise in temperature. The cooking occurs rapidly and without a loss of nutrients or the formation of unhealthy compounds. Generating such intense fields requires closely spaced electrodes, however, which limits the size of the portion you can prepare this way. “It’s not a system where you can put in a few kilograms,” says Hans Roelofs, innovation director for IXL.
Various sectors of the food-processing industry have been using pulsed electric fields for decades to sterilize milk and juice and to better extract juice from some fruit and sugar from sugar beets. What’s new is the notion that the same technique can prepare foods that appeal to the palate.
Whether Nutri-Pulse can really accomplish that is unclear. The company is still testing its prototypes internally, and the cooks who have been shown its capabilities are enthusiastic. “They were really astonished,” says Roelofs. “They want to have it.” But consulting engineer and Institute of Food Technology [PDF] fellow J. Peter Clark, writing about this technique in Food Technology magazine, gave the new form of superfast cooking only faint praise: “Raw foods are made edible, but acceptance may require some adjustment to familiar expectations.” That doesn’t sound so yummy, does it?
Someday soon, these Dutch engineers may perfect a system that averts overcooking and maintains juiciness without taking as much time as sous vide. For some foods that’ll be great; for others it will no doubt be awful. So hang on to that grill of yours.